Factual error: In series 13, when phone numbers are referred to, they usually start 0808 (even mobile numbers). UK phone numbers starting with those numbers are freephone numbers and wouldn't be used for private use, or even for mobiles (which all start with 07).
Revealing mistake: During the flat fire, the girl tosses her baby to ADO Coleman. Just before he catches it, you can see that the falling baby is a doll.